Police in St. Albans, Vt., said they believe that accidental carbon monoxide poisoning caused the death of a 17-year-old found slumped over the steering wheel in a car. Police said the investigation into Logan Newell’s death remains open until toxicology reports have been completed. However, they said evidence gathered and an emissions test conducted on the car late Monday suggest that the cause was accidental carbon monoxide poisoning. Newell, of Georgia, Vt., was found in the car at a park-and-ride area Sunday.